diff options
| -rw-r--r-- | include/linux/sunrpc/svc_rdma.h | 1 | ||||
| -rw-r--r-- | net/sunrpc/xprtrdma/svc_rdma_backchannel.c | 6 | ||||
| -rw-r--r-- | net/sunrpc/xprtrdma/svc_rdma_sendto.c | 696 | ||||
| -rw-r--r-- | net/sunrpc/xprtrdma/svc_rdma_transport.c | 2 |
4 files changed, 350 insertions, 355 deletions
diff --git a/include/linux/sunrpc/svc_rdma.h b/include/linux/sunrpc/svc_rdma.h index ca08671..599ee03 100644 --- a/include/linux/sunrpc/svc_rdma.h +++ b/include/linux/sunrpc/svc_rdma.h @@ -212,7 +212,6 @@ extern int svc_rdma_xdr_decode_req(struct xdr_buf *); extern int svc_rdma_xdr_encode_error(struct svcxprt_rdma *, struct rpcrdma_msg *, enum rpcrdma_errcode, __be32 *); -extern void svc_rdma_xdr_encode_write_list(struct rpcrdma_msg *, int); extern void svc_rdma_xdr_encode_reply_array(struct rpcrdma_write_array *, int); extern void svc_rdma_xdr_encode_array_chunk(struct rpcrdma_write_array *, int, __be32, __be64, u32); diff --git a/net/sunrpc/xprtrdma/svc_rdma_backchannel.c b/net/sunrpc/xprtrdma/svc_rdma_backchannel.c index 0305b33..bf185b7 100644 --- a/net/sunrpc/xprtrdma/svc_rdma_backchannel.c +++ b/net/sunrpc/xprtrdma/svc_rdma_backchannel.c @@ -90,9 +90,9 @@ out_notfound: * Caller holds the connection's mutex and has already marshaled * the RPC/RDMA request. * - * This is similar to svc_rdma_reply, but takes an rpc_rqst - * instead, does not support chunks, and avoids blocking memory - * allocation. + * This is similar to svc_rdma_send_reply_msg, but takes a struct + * rpc_rqst instead, does not support chunks, and avoids blocking + * memory allocation. * * XXX: There is still an opportunity to block in svc_rdma_send() * if there are no SQ entries to post the Send. This may occur if diff --git a/net/sunrpc/xprtrdma/svc_rdma_sendto.c b/net/sunrpc/xprtrdma/svc_rdma_sendto.c index 2eb3df6..ce62b78 100644 --- a/net/sunrpc/xprtrdma/svc_rdma_sendto.c +++ b/net/sunrpc/xprtrdma/svc_rdma_sendto.c @@ -1,4 +1,5 @@ /* + * Copyright (c) 2016 Oracle. All rights reserved. * Copyright (c) 2014 Open Grid Computing, Inc. All rights reserved. * Copyright (c) 2005-2006 Network Appliance, Inc. All rights reserved. * @@ -40,6 +41,63 @@ * Author: Tom Tucker <tom@opengridcomputing.com> */ +/* Operation + * + * The main entry point is svc_rdma_sendto. This is called by the + * RPC server when an RPC Reply is ready to be transmitted to a client. + * + * The passed-in svc_rqst contains a struct xdr_buf which holds an + * XDR-encoded RPC Reply message. sendto must construct the RPC-over-RDMA + * transport header, post all Write WRs needed for this Reply, then post + * a Send WR conveying the transport header and the RPC message itself to + * the client. + * + * svc_rdma_sendto must fully transmit the Reply before returning, as + * the svc_rqst will be recycled as soon as sendto returns. Remaining + * resources referred to by the svc_rqst are also recycled at that time. + * Therefore any resources that must remain longer must be detached + * from the svc_rqst and released later. + * + * Page Management + * + * The I/O that performs Reply transmission is asynchronous, and may + * complete well after sendto returns. Thus pages under I/O must be + * removed from the svc_rqst before sendto returns. + * + * The logic here depends on Send Queue and completion ordering. Since + * the Send WR is always posted last, it will always complete last. Thus + * when it completes, it is guaranteed that all previous Write WRs have + * also completed. + * + * Write WRs are constructed and posted. Each Write segment gets its own + * svc_rdma_rw_ctxt, allowing the Write completion handler to find and + * DMA-unmap the pages under I/O for that Write segment. The Write + * completion handler does not release any pages. + * + * When the Send WR is constructed, it also gets its own svc_rdma_op_ctxt. + * The ownership of all of the Reply's pages are transferred into that + * ctxt, the Send WR is posted, and sendto returns. + * + * The svc_rdma_op_ctxt is presented when the Send WR completes. The + * Send completion handler finally releases the Reply's pages. + * + * This mechanism also assumes that completions on the transport's Send + * Completion Queue do not run in parallel. Otherwise a Write completion + * and Send completion running at the same time could release pages that + * are still DMA-mapped. + * + * Error Handling + * + * - If the Send WR is posted successfully, it will either complete + * successfully, or get flushed. Either way, the Send completion + * handler releases the Reply's pages. + * - If the Send WR cannot be not posted, the forward path releases + * the Reply's pages. + * + * This handles the case, without the use of page reference counting, + * where two different Write segments send portions of the same page. + */ + #include <linux/sunrpc/debug.h> #include <linux/sunrpc/rpc_rdma.h> #include <linux/spinlock.h> @@ -55,6 +113,133 @@ static u32 xdr_padsize(u32 len) return (len & 3) ? (4 - (len & 3)) : 0; } +/* Returns length of transport header, in bytes. + */ +static unsigned int svc_rdma_reply_hdr_len(__be32 *rdma_resp) +{ + unsigned int nsegs; + __be32 *p; + + p = rdma_resp; + + /* RPC-over-RDMA V1 replies never have a Read list. */ + p += rpcrdma_fixed_maxsz + 1; + + /* Skip Write list. */ + while (*p++ != xdr_zero) { + nsegs = be32_to_cpup(p++); + p += nsegs * rpcrdma_segment_maxsz; + } + + /* Skip Reply chunk. */ + if (*p++ != xdr_zero) { + nsegs = be32_to_cpup(p++); + p += nsegs * rpcrdma_segment_maxsz; + } + + return (unsigned long)p - (unsigned long)rdma_resp; +} + +/* One Write chunk is copied from Call transport header to Reply + * transport header. Each segment's length field is updated to + * reflect number of bytes consumed in the segment. + * + * Returns number of segments in this chunk. + */ +static unsigned int xdr_encode_write_chunk(__be32 *dst, __be32 *src, + unsigned int remaining) +{ + unsigned int i, nsegs; + u32 seg_len; + + /* Write list discriminator */ + *dst++ = *src++; + + /* number of segments in this chunk */ + nsegs = be32_to_cpup(src); + *dst++ = *src++; + + for (i = nsegs; i; i--) { + /* segment's RDMA handle */ + *dst++ = *src++; + + /* bytes returned in this segment */ + seg_len = be32_to_cpu(*src); + if (remaining >= seg_len) { + /* entire segment was consumed */ + *dst = *src; + remaining -= seg_len; + } else { + /* segment only partly filled */ + *dst = cpu_to_be32(remaining); + remaining = 0; + } + dst++; src++; + + /* segment's RDMA offset */ + *dst++ = *src++; + *dst++ = *src++; + } + + return nsegs; +} + +/* The client provided a Write list in the Call message. Fill in + * the segments in the first Write chunk in the Reply's transport + * header with the number of bytes consumed in each segment. + * Remaining chunks are returned unused. + * + * Assumptions: + * - Client has provided only one Write chunk + */ +static void svc_rdma_xdr_encode_write_list(__be32 *rdma_resp, __be32 *wr_ch, + unsigned int consumed) +{ + unsigned int nsegs; + __be32 *p, *q; + + /* RPC-over-RDMA V1 replies never have a Read list. */ + p = rdma_resp + rpcrdma_fixed_maxsz + 1; + + q = wr_ch; + while (*q != xdr_zero) { + nsegs = xdr_encode_write_chunk(p, q, consumed); + q += 2 + nsegs * rpcrdma_segment_maxsz; + p += 2 + nsegs * rpcrdma_segment_maxsz; + consumed = 0; + } + + /* Terminate Write list */ + *p++ = xdr_zero; + + /* Reply chunk discriminator; may be replaced later */ + *p = xdr_zero; +} + +/* The client provided a Reply chunk in the Call message. Fill in + * the segments in the Reply chunk in the Reply message with the + * number of bytes consumed in each segment. + * + * Assumptions: + * - Reply can always fit in the provided Reply chunk + */ +static void svc_rdma_xdr_encode_reply_chunk(__be32 *rdma_resp, __be32 *rp_ch, + unsigned int consumed) +{ + __be32 *p; + + /* Find the Reply chunk in the Reply's xprt header. + * RPC-over-RDMA V1 replies never have a Read list. + */ + p = rdma_resp + rpcrdma_fixed_maxsz + 1; + + /* Skip past Write list */ + while (*p++ != xdr_zero) + p += 1 + be32_to_cpup(p) * rpcrdma_segment_maxsz; + + xdr_encode_write_chunk(p, rp_ch, consumed); +} + int svc_rdma_map_xdr(struct svcxprt_rdma *xprt, struct xdr_buf *xdr, struct svc_rdma_req_map *vec, @@ -123,45 +308,14 @@ int svc_rdma_map_xdr(struct svcxprt_rdma *xprt, return 0; } -static dma_addr_t dma_map_xdr(struct svcxprt_rdma *xprt, - struct xdr_buf *xdr, - u32 xdr_off, size_t len, int dir) -{ - struct page *page; - dma_addr_t dma_addr; - if (xdr_off < xdr->head[0].iov_len) { - /* This offset is in the head */ - xdr_off += (unsigned long)xdr->head[0].iov_base & ~PAGE_MASK; - page = virt_to_page(xdr->head[0].iov_base); - } else { - xdr_off -= xdr->head[0].iov_len; - if (xdr_off < xdr->page_len) { - /* This offset is in the page list */ - xdr_off += xdr->page_base; - page = xdr->pages[xdr_off >> PAGE_SHIFT]; - xdr_off &= ~PAGE_MASK; - } else { - /* This offset is in the tail */ - xdr_off -= xdr->page_len; - xdr_off += (unsigned long) - xdr->tail[0].iov_base & ~PAGE_MASK; - page = virt_to_page(xdr->tail[0].iov_base); - } - } - dma_addr = ib_dma_map_page(xprt->sc_cm_id->device, page, xdr_off, - min_t(size_t, PAGE_SIZE, len), dir); - return dma_addr; -} - /* Parse the RPC Call's transport header. */ -static void svc_rdma_get_write_arrays(struct rpcrdma_msg *rmsgp, - struct rpcrdma_write_array **write, - struct rpcrdma_write_array **reply) +static void svc_rdma_get_write_arrays(__be32 *rdma_argp, + __be32 **write, __be32 **reply) { __be32 *p; - p = (__be32 *)&rmsgp->rm_body.rm_chunks[0]; + p = rdma_argp + rpcrdma_fixed_maxsz; /* Read list */ while (*p++ != xdr_zero) @@ -169,7 +323,7 @@ static void svc_rdma_get_write_arrays(struct rpcrdma_msg *rmsgp, /* Write list */ if (*p != xdr_zero) { - *write = (struct rpcrdma_write_array *)p; + *write = p; while (*p++ != xdr_zero) p += 1 + be32_to_cpu(*p) * 4; } else { @@ -179,7 +333,7 @@ static void svc_rdma_get_write_arrays(struct rpcrdma_msg *rmsgp, /* Reply chunk */ if (*p != xdr_zero) - *reply = (struct rpcrdma_write_array *)p; + *reply = p; else *reply = NULL; } @@ -210,6 +364,32 @@ static u32 svc_rdma_get_inv_rkey(__be32 *rdma_argp, return be32_to_cpup(p); } +/* ib_dma_map_page() is used here because svc_rdma_dma_unmap() + * is used during completion to DMA-unmap this memory, and + * it uses ib_dma_unmap_page() exclusively. + */ +static int svc_rdma_dma_map_buf(struct svcxprt_rdma *rdma, + struct svc_rdma_op_ctxt *ctxt, + unsigned int sge_no, + unsigned char *base, + unsigned int len) +{ + unsigned long offset = (unsigned long)base & ~PAGE_MASK; + struct ib_device *dev = rdma->sc_cm_id->device; + dma_addr_t dma_addr; + + dma_addr = ib_dma_map_page(dev, virt_to_page(base), + offset, len, DMA_TO_DEVICE); + if (ib_dma_mapping_error(dev, dma_addr)) + return -EIO; + + ctxt->sge[sge_no].addr = dma_addr; + ctxt->sge[sge_no].length = len; + ctxt->sge[sge_no].lkey = rdma->sc_pd->local_dma_lkey; + svc_rdma_count_mappings(rdma, ctxt); + return 0; +} + static int svc_rdma_dma_map_page(struct svcxprt_rdma *rdma, struct svc_rdma_op_ctxt *ctxt, unsigned int sge_no, @@ -253,222 +433,73 @@ int svc_rdma_map_reply_hdr(struct svcxprt_rdma *rdma, return svc_rdma_dma_map_page(rdma, ctxt, 0, ctxt->pages[0], 0, len); } -/* Assumptions: - * - The specified write_len can be represented in sc_max_sge * PAGE_SIZE +/* Load the xdr_buf into the ctxt's sge array, and DMA map each + * element as it is added. + * + * Returns the number of sge elements loaded on success, or + * a negative errno on failure. */ -static int send_write(struct svcxprt_rdma *xprt, struct svc_rqst *rqstp, - u32 rmr, u64 to, - u32 xdr_off, int write_len, - struct svc_rdma_req_map *vec) +static int svc_rdma_map_reply_msg(struct svcxprt_rdma *rdma, + struct svc_rdma_op_ctxt *ctxt, + struct xdr_buf *xdr, __be32 *wr_lst) { - struct ib_rdma_wr write_wr; - struct ib_sge *sge; - int xdr_sge_no; - int sge_no; - int sge_bytes; - int sge_off; - int bc; - struct svc_rdma_op_ctxt *ctxt; + unsigned int len, sge_no, remaining, page_off; + struct page **ppages; + unsigned char *base; + u32 xdr_pad; + int ret; - if (vec->count > RPCSVC_MAXPAGES) { - pr_err("svcrdma: Too many pages (%lu)\n", vec->count); - return -EIO; - } + sge_no = 1; - dprintk("svcrdma: RDMA_WRITE rmr=%x, to=%llx, xdr_off=%d, " - "write_len=%d, vec->sge=%p, vec->count=%lu\n", - rmr, (unsigned long long)to, xdr_off, - write_len, vec->sge, vec->count); + ret = svc_rdma_dma_map_buf(rdma, ctxt, sge_no++, + xdr->head[0].iov_base, + xdr->head[0].iov_len); + if (ret < 0) + return ret; - ctxt = svc_rdma_get_context(xprt); - ctxt->direction = DMA_TO_DEVICE; - sge = ctxt->sge; - - /* Find the SGE associated with xdr_off */ - for (bc = xdr_off, xdr_sge_no = 1; bc && xdr_sge_no < vec->count; - xdr_sge_no++) { - if (vec->sge[xdr_sge_no].iov_len > bc) - break; - bc -= vec->sge[xdr_sge_no].iov_len; - } + /* If a Write chunk is present, the xdr_buf's page list + * is not included inline. However the Upper Layer may + * have added XDR padding in the tail buffer, and that + * should not be included inline. + */ + if (wr_lst) { + base = xdr->tail[0].iov_base; + len = xdr->tail[0].iov_len; + xdr_pad = xdr_padsize(xdr->page_len); - sge_off = bc; - bc = write_len; - sge_no = 0; - - /* Copy the remaining SGE */ - while (bc != 0) { - sge_bytes = min_t(size_t, - bc, vec->sge[xdr_sge_no].iov_len-sge_off); - sge[sge_no].length = sge_bytes; - sge[sge_no].addr = - dma_map_xdr(xprt, &rqstp->rq_res, xdr_off, - sge_bytes, DMA_TO_DEVICE); - xdr_off += sge_bytes; - if (ib_dma_mapping_error(xprt->sc_cm_id->device, - sge[sge_no].addr)) - goto err; - svc_rdma_count_mappings(xprt, ctxt); - sge[sge_no].lkey = xprt->sc_pd->local_dma_lkey; - ctxt->count++; - sge_off = 0; - sge_no++; - xdr_sge_no++; - if (xdr_sge_no > vec->count) { - pr_err("svcrdma: Too many sges (%d)\n", xdr_sge_no); - goto err; + if (len && xdr_pad) { + base += xdr_pad; + len -= xdr_pad; } - bc -= sge_bytes; - if (sge_no == xprt->sc_max_sge) - break; - } - - /* Prepare WRITE WR */ - memset(&write_wr, 0, sizeof write_wr); - ctxt->cqe.done = svc_rdma_wc_write; - write_wr.wr.wr_cqe = &ctxt->cqe; - write_wr.wr.sg_list = &sge[0]; - write_wr.wr.num_sge = sge_no; - write_wr.wr.opcode = IB_WR_RDMA_WRITE; - write_wr.wr.send_flags = IB_SEND_SIGNALED; - write_wr.rkey = rmr; - write_wr.remote_addr = to; - - /* Post It */ - atomic_inc(&rdma_stat_write); - if (svc_rdma_send(xprt, &write_wr.wr)) - goto err; - return write_len - bc; - err: - svc_rdma_unmap_dma(ctxt); - svc_rdma_put_context(ctxt, 0); - return -EIO; -} -noinline -static int send_write_chunks(struct svcxprt_rdma *xprt, - struct rpcrdma_write_array *wr_ary, - struct rpcrdma_msg *rdma_resp, - struct svc_rqst *rqstp, - struct svc_rdma_req_map *vec) -{ - u32 xfer_len = rqstp->rq_res.page_len; - int write_len; - u32 xdr_off; - int chunk_off; - int chunk_no; - int nchunks; - struct rpcrdma_write_array *res_ary; - int ret; - - res_ary = (struct rpcrdma_write_array *) - &rdma_resp->rm_body.rm_chunks[1]; - - /* Write chunks start at the pagelist */ - nchunks = be32_to_cpu(wr_ary->wc_nchunks); - for (xdr_off = rqstp->rq_res.head[0].iov_len, chunk_no = 0; - xfer_len && chunk_no < nchunks; - chunk_no++) { - struct rpcrdma_segment *arg_ch; - u64 rs_offset; - - arg_ch = &wr_ary->wc_array[chunk_no].wc_target; - write_len = min(xfer_len, be32_to_cpu(arg_ch->rs_length)); - - /* Prepare the response chunk given the length actually - * written */ - xdr_decode_hyper((__be32 *)&arg_ch->rs_offset, &rs_offset); - svc_rdma_xdr_encode_array_chunk(res_ary, chunk_no, - arg_ch->rs_handle, - arg_ch->rs_offset, - write_len); - chunk_off = 0; - while (write_len) { - ret = send_write(xprt, rqstp, - be32_to_cpu(arg_ch->rs_handle), - rs_offset + chunk_off, - xdr_off, - write_len, - vec); - if (ret <= 0) - goto out_err; - chunk_off += ret; - xdr_off += ret; - xfer_len -= ret; - write_len -= ret; - } + goto tail; } - /* Update the req with the number of chunks actually used */ - svc_rdma_xdr_encode_write_list(rdma_resp, chunk_no); - return rqstp->rq_res.page_len; + ppages = xdr->pages + (xdr->page_base >> PAGE_SHIFT); + page_off = xdr->page_base & ~PAGE_MASK; + remaining = xdr->page_len; + while (remaining) { + len = min_t(u32, PAGE_SIZE - page_off, remaining); -out_err: - pr_err("svcrdma: failed to send write chunks, rc=%d\n", ret); - return -EIO; -} - -noinline -static int send_reply_chunks(struct svcxprt_rdma *xprt, - struct rpcrdma_write_array *rp_ary, - struct rpcrdma_msg *rdma_resp, - struct svc_rqst *rqstp, - struct svc_rdma_req_map *vec) -{ - u32 xfer_len = rqstp->rq_res.len; - int write_len; - u32 xdr_off; - int chunk_no; - int chunk_off; - int nchunks; - struct rpcrdma_segment *ch; - struct rpcrdma_write_array *res_ary; - int ret; + ret = svc_rdma_dma_map_page(rdma, ctxt, sge_no++, + *ppages++, page_off, len); + if (ret < 0) + return ret; - /* XXX: need to fix when reply lists occur with read-list and or - * write-list */ - res_ary = (struct rpcrdma_write_array *) - &rdma_resp->rm_body.rm_chunks[2]; - - /* xdr offset starts at RPC message */ - nchunks = be32_to_cpu(rp_ary->wc_nchunks); - for (xdr_off = 0, chunk_no = 0; - xfer_len && chunk_no < nchunks; - chunk_no++) { - u64 rs_offset; - ch = &rp_ary->wc_array[chunk_no].wc_target; - write_len = min(xfer_len, be32_to_cpu(ch->rs_length)); - - /* Prepare the reply chunk given the length actually - * written */ - xdr_decode_hyper((__be32 *)&ch->rs_offset, &rs_offset); - svc_rdma_xdr_encode_array_chunk(res_ary, chunk_no, - ch->rs_handle, ch->rs_offset, - write_len); - chunk_off = 0; - while (write_len) { - ret = send_write(xprt, rqstp, - be32_to_cpu(ch->rs_handle), - rs_offset + chunk_off, - xdr_off, - write_len, - vec); - if (ret <= 0) - goto out_err; - chunk_off += ret; - xdr_off += ret; - xfer_len -= ret; - write_len -= ret; - } + remaining -= len; + page_off = 0; } - /* Update the req with the number of chunks actually used */ - svc_rdma_xdr_encode_reply_array(res_ary, chunk_no); - return rqstp->rq_res.len; + base = xdr->tail[0].iov_base; + len = xdr->tail[0].iov_len; +tail: + if (len) { + ret = svc_rdma_dma_map_buf(rdma, ctxt, sge_no++, base, len); + if (ret < 0) + return ret; + } -out_err: - pr_err("svcrdma: failed to send reply chunks, rc=%d\n", ret); - return -EIO; + return sge_no - 1; } /* The svc_rqst and all resources it owns are released as soon as @@ -525,90 +556,66 @@ int svc_rdma_post_send_wr(struct svcxprt_rdma *rdma, return svc_rdma_send(rdma, send_wr); } -/* This function prepares the portion of the RPCRDMA message to be - * sent in the RDMA_SEND. This function is called after data sent via - * RDMA has already been transmitted. There are three cases: - * - The RPCRDMA header, RPC header, and payload are all sent in a - * single RDMA_SEND. This is the "inline" case. - * - The RPCRDMA header and some portion of the RPC header and data - * are sent via this RDMA_SEND and another portion of the data is - * sent via RDMA. - * - The RPCRDMA header [NOMSG] is sent in this RDMA_SEND and the RPC - * header and data are all transmitted via RDMA. - * In all three cases, this function prepares the RPCRDMA header in - * sge[0], the 'type' parameter indicates the type to place in the - * RPCRDMA header, and the 'byte_count' field indicates how much of - * the XDR to include in this RDMA_SEND. NB: The offset of the payload - * to send is zero in the XDR. +/* Prepare the portion of the RPC Reply that will be transmitted + * via RDMA Send. The RPC-over-RDMA transport header is prepared + * in sge[0], and the RPC xdr_buf is prepared in following sges. + * + * Depending on whether a Write list or Reply chunk is present, + * the server may send all, a portion of, or none of the xdr_buf. + * In the latter case, only the transport header (sge[0]) is + * transmitted. + * + * RDMA Send is the last step of transmitting an RPC reply. Pages + * involved in the earlier RDMA Writes are here transferred out + * of the rqstp and into the ctxt's page array. These pages are + * DMA unmapped by each Write completion, but the subsequent Send + * completion finally releases these pages. + * + * Assumptions: + * - The Reply's transport header will never be larger than a page. */ -static int send_reply(struct svcxprt_rdma *rdma, - struct svc_rqst *rqstp, - struct page *page, - struct rpcrdma_msg *rdma_resp, - struct svc_rdma_req_map *vec, - int byte_count, - u32 inv_rkey) +static int svc_rdma_send_reply_msg(struct svcxprt_rdma *rdma, + __be32 *rdma_argp, __be32 *rdma_resp, + struct svc_rqst *rqstp, + __be32 *wr_lst, __be32 *rp_ch) { struct svc_rdma_op_ctxt *ctxt; - u32 xdr_off; - int sge_no; - int sge_bytes; - int ret = -EIO; + u32 inv_rkey; + int ret; + + dprintk("svcrdma: sending %s reply: head=%zu, pagelen=%u, tail=%zu\n", + (rp_ch ? "RDMA_NOMSG" : "RDMA_MSG"), + rqstp->rq_res.head[0].iov_len, + rqstp->rq_res.page_len, + rqstp->rq_res.tail[0].iov_len); - /* Prepare the context */ ctxt = svc_rdma_get_context(rdma); - ctxt->direction = DMA_TO_DEVICE; - ctxt->pages[0] = page; - ctxt->count = 1; - /* Prepare the SGE for the RPCRDMA Header */ - ctxt->sge[0].lkey = rdma->sc_pd->local_dma_lkey; - ctxt->sge[0].length = - svc_rdma_xdr_get_reply_hdr_len((__be32 *)rdma_resp); - ctxt->sge[0].addr = - ib_dma_map_page(rdma->sc_cm_id->device, page, 0, - ctxt->sge[0].length, DMA_TO_DEVICE); - if (ib_dma_mapping_error(rdma->sc_cm_id->device, ctxt->sge[0].addr)) + ret = svc_rdma_map_reply_hdr(rdma, ctxt, rdma_resp, + svc_rdma_reply_hdr_len(rdma_resp)); + if (ret < 0) goto err; - svc_rdma_count_mappings(rdma, ctxt); - - ctxt->direction = DMA_TO_DEVICE; - /* Map the payload indicated by 'byte_count' */ - xdr_off = 0; - for (sge_no = 1; byte_count && sge_no < vec->count; sge_no++) { - sge_bytes = min_t(size_t, vec->sge[sge_no].iov_len, byte_count); - byte_count -= sge_bytes; - ctxt->sge[sge_no].addr = - dma_map_xdr(rdma, &rqstp->rq_res, xdr_off, - sge_bytes, DMA_TO_DEVICE); - xdr_off += sge_bytes; - if (ib_dma_mapping_error(rdma->sc_cm_id->device, - ctxt->sge[sge_no].addr)) + if (!rp_ch) { + ret = svc_rdma_map_reply_msg(rdma, ctxt, + &rqstp->rq_res, wr_lst); + if (ret < 0) goto err; - svc_rdma_count_mappings(rdma, ctxt); - ctxt->sge[sge_no].lkey = rdma->sc_pd->local_dma_lkey; - ctxt->sge[sge_no].length = sge_bytes; - } - if (byte_count != 0) { - pr_err("svcrdma: Could not map %d bytes\n", byte_count); - goto err; } svc_rdma_save_io_pages(rqstp, ctxt); - if (sge_no > rdma->sc_max_sge) { - pr_err("svcrdma: Too many sges (%d)\n", sge_no); - goto err; - } - - ret = svc_rdma_post_send_wr(rdma, ctxt, sge_no, inv_rkey); + inv_rkey = 0; + if (rdma->sc_snd_w_inv) + inv_rkey = svc_rdma_get_inv_rkey(rdma_argp, wr_lst, rp_ch); + ret = svc_rdma_post_send_wr(rdma, ctxt, 1 + ret, inv_rkey); if (ret) goto err; return 0; - err: +err: + pr_err("svcrdma: failed to post Send WR (%d)\n", ret); svc_rdma_unmap_dma(ctxt); svc_rdma_put_context(ctxt, 1); return ret; @@ -618,41 +625,36 @@ void svc_rdma_prep_reply_hdr(struct svc_rqst *rqstp) { } +/** + * svc_rdma_sendto - Transmit an RPC reply + * @rqstp: processed RPC request, reply XDR already in ::rq_res + * + * Any resources still associated with @rqstp are released upon return. + * If no reply message was possible, the connection is closed. + * + * Returns: + * %0 if an RPC reply has been successfully posted, + * %-ENOMEM if a resource shortage occurred (connection is lost), + * %-ENOTCONN if posting failed (connection is lost). + */ int svc_rdma_sendto(struct svc_rqst *rqstp) { struct svc_xprt *xprt = rqstp->rq_xprt; struct svcxprt_rdma *rdma = container_of(xprt, struct svcxprt_rdma, sc_xprt); - struct rpcrdma_msg *rdma_argp; - struct rpcrdma_msg *rdma_resp; - struct rpcrdma_write_array *wr_ary, *rp_ary; - int ret; - int inline_bytes; + __be32 *p, *rdma_argp, *rdma_resp, *wr_lst, *rp_ch; + struct xdr_buf *xdr = &rqstp->rq_res; struct page *res_page; - struct svc_rdma_req_map *vec; - u32 inv_rkey; - __be32 *p; - - dprintk("svcrdma: sending response for rqstp=%p\n", rqstp); + int ret; - /* Get the RDMA request header. The receive logic always - * places this at the start of page 0. + /* Find the call's chunk lists to decide how to send the reply. + * Receive places the Call's xprt header at the start of page 0. */ rdma_argp = page_address(rqstp->rq_pages[0]); - svc_rdma_get_write_arrays(rdma_argp, &wr_ary, &rp_ary); + svc_rdma_get_write_arrays(rdma_argp, &wr_lst, &rp_ch); - inv_rkey = 0; - if (rdma->sc_snd_w_inv) - inv_rkey = svc_rdma_get_inv_rkey(&rdma_argp->rm_xid, - (__be32 *)wr_ary, - (__be32 *)rp_ary); - - /* Build an req vec for the XDR */ - vec = svc_rdma_get_req_map(rdma); - ret = svc_rdma_map_xdr(rdma, &rqstp->rq_res, vec, wr_ary != NULL); - if (ret) - goto err0; - inline_bytes = rqstp->rq_res.len; + dprintk("svcrdma: preparing response for XID 0x%08x\n", + be32_to_cpup(rdma_argp)); /* Create the RDMA response header. xprt->xpt_mutex, * acquired in svc_send(), serializes RPC replies. The @@ -666,54 +668,46 @@ int svc_rdma_sendto(struct svc_rqst *rqstp) goto err0; rdma_resp = page_address(res_page); - p = &rdma_resp->rm_xid; - *p++ = rdma_argp->rm_xid; - *p++ = rdma_argp->rm_vers; + p = rdma_resp; + *p++ = *rdma_argp; + *p++ = *(rdma_argp + 1); *p++ = rdma->sc_fc_credits; - *p++ = rp_ary ? rdma_nomsg : rdma_msg; + *p++ = rp_ch ? rdma_nomsg : rdma_msg; /* Start with empty chunks */ *p++ = xdr_zero; *p++ = xdr_zero; *p = xdr_zero; - /* Send any write-chunk data and build resp write-list */ - if (wr_ary) { - ret = send_write_chunks(rdma, wr_ary, rdma_resp, rqstp, vec); + if (wr_lst) { + /* XXX: Presume the client sent only one Write chunk */ + ret = svc_rdma_send_write_chunk(rdma, wr_lst, xdr); if (ret < 0) goto err1; - inline_bytes -= ret + xdr_padsize(ret); + svc_rdma_xdr_encode_write_list(rdma_resp, wr_lst, ret); } - - /* Send any reply-list data and update resp reply-list */ - if (rp_ary) { - ret = send_reply_chunks(rdma, rp_ary, rdma_resp, rqstp, vec); + if (rp_ch) { + ret = svc_rdma_send_reply_chunk(rdma, rp_ch, wr_lst, xdr); if (ret < 0) goto err1; - inline_bytes -= ret; + svc_rdma_xdr_encode_reply_chunk(rdma_resp, rp_ch, ret); } - /* Post a fresh Receive buffer _before_ sending the reply */ ret = svc_rdma_post_recv(rdma, GFP_KERNEL); if (ret) goto err1; - - ret = send_reply(rdma, rqstp, res_page, rdma_resp, vec, - inline_bytes, inv_rkey); + ret = svc_rdma_send_reply_msg(rdma, rdma_argp, rdma_resp, rqstp, + wr_lst, rp_ch); if (ret < 0) goto err0; - - svc_rdma_put_req_map(rdma, vec); - dprintk("svcrdma: send_reply returns %d\n", ret); - return ret; + return 0; err1: put_page(res_page); err0: - svc_rdma_put_req_map(rdma, vec); pr_err("svcrdma: Could not send reply, err=%d. Closing transport.\n", ret); - set_bit(XPT_CLOSE, &rdma->sc_xprt.xpt_flags); + set_bit(XPT_CLOSE, &xprt->xpt_flags); return -ENOTCONN; } diff --git a/net/sunrpc/xprtrdma/svc_rdma_transport.c b/net/sunrpc/xprtrdma/svc_rdma_transport.c index b25c509..237c377 100644 --- a/net/sunrpc/xprtrdma/svc_rdma_transport.c +++ b/net/sunrpc/xprtrdma/svc_rdma_transport.c @@ -1053,6 +1053,8 @@ static struct svc_xprt *svc_rdma_accept(struct svc_xprt *xprt) memset(&qp_attr, 0, sizeof qp_attr); qp_attr.event_handler = qp_event_handler; qp_attr.qp_context = &newxprt->sc_xprt; + qp_attr.port_num = newxprt->sc_cm_id->port_num; + qp_attr.cap.max_rdma_ctxs = newxprt->sc_max_requests; qp_attr.cap.max_send_wr = newxprt->sc_sq_depth; qp_attr.cap.max_recv_wr = newxprt->sc_rq_depth; qp_attr.cap.max_send_sge = newxprt->sc_max_sge; |
